1. Field Of The Invention
This invention relates to devices for measuring current velocity and direction in a body of water and is more particularly directed to such an apparatus that utilizes the direction and magnitude of tilt effected by the current thereon for determining current velocity and direction of flow.
2. Description Of The Prior Art
In recent years, the inclinometer or tilt meter has replaced the rotor mounted logs for determing subsurface current velocities and directions in a body of water. The inclinometers are more accurate in obtaining the information desired and not subject to fouling by debris, and other matter in the water as are the rotor mounted logs. From the inclinometers the extent of tilt effected by the current is obtained in both the North-South direction and the East-West direction, which information is sufficient to determine, by the application of the mathematics of vectors, the actual direction of the flow of the current and its velocity. The problem with the use of inclinometers or tilt meters has been in the procuring of this information from these devices at the same time as the instruments are affected by the currents. At present, the inclinometers have to be lifted from their position in the body of water in order to read the recordings thereof. As shown by my U.S. Pat. No. 3,372,585, the inclinometer is provided with a soluble member which upon its dissolution by the water after a predetermined period of time, the mechanism of the inclinometer is locked in position and the reading then recorded becomes fixed so that upon withdrawing the tilt meter from the water, the device remains inoperative and the reading unchanged. However, the device must be removed from the body of water to be read so that the information may be recored as incurred thereon by the action of the current. In those inclinometers wherein a number of such readings of current action is desired over a period of time, the devices are provided with photographic equipment for taking pictures of the readings on the inclinometer along with a clock for indicating time. These devices, likewise, must be removed from the body of water in order to obtain the current information. The present invention avoids the disadvantage of having to remove the inclinometer from the body of water by transmitting the readings of the device simultaneously as they are effected by the currents as to their forces and directions. The recipient of this information can be ashore or in a boat and if desired the information can be recorded and stored on a magnetic tape for use in a computer.